                                         :layer/type :layer.type/path
                                         :layer/path (layers/arrow-path [start-x start-y] [end-x end-y])
                                         :selected? selected?))]
-                     (dom/g nil
+                     (dom/g #js {:key (str (:db/id origin) "-" (:db/id dest))}
                        (svg-element (assoc props
                                            :className "layer-handle"
                                            :onMouseDown #(do (utils/stop-event %)


          ;; in-progress outlines for shapes
          (when (keyboard/arrow-shortcut-active? app)
            (apply dom/g #js {:className "arrow-handles"}
                   (for [layer (ds/touch-all '[:find ?t :where [?t :layer/type :layer.type/rect]] db)]
                     (om/build arrow-handle
                               (assoc layer

                               {:react-key (:db/id layer)}))))


          (apply dom/g #js {:className "layer-arrows"
                            :key "layer-arrows"}
                 (for [pointer-datom pointer-datoms
                       :let [origin (or (get drawing-layers (:e pointer-datom))
                                        (get subscriber-layers (:e pointer-datom))
